package main

import "fmt"

func bcd(a, b int)  {
	a,b = b, a
	fmt.Printf("a = %d, b = %d\n", a, b)
}

func efg(p1, p2 *int) {
	*p1, *p2 = *p2, *p1
	fmt.Printf("*p1 = %d, *p2 = %d\n", *p1, *p2)
}

func main()  {
	a := 10
	b := 20
	bcd(a, b)
	fmt.Printf("a = %d, b = %d\n", a, b)
	efg(&a, &b)
	fmt.Printf("a = %d, b = %d\n", a, b)
}
